/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/****************************************************************************
 * drivers/usbhost/usbhost_enumerate.c
 *
 *   Copyright (C) 2011-2012, 2015 Gregory Nutt. All rights reserved.
 *   Authors: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <tinyara/config.h>

#include <sys/types.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>

#include <tinyara/arch.h>
#include <tinyara/usb/usb.h>
#include <tinyara/usb/usbhost.h>
#include <tinyara/usb/hub.h>
#include <tinyara/usb/usbhost_devaddr.h>

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/****************************************************************************
 * Private Types
 ****************************************************************************/

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

static inline uint16_t usbhost_getle16(const uint8_t *val);
static void usbhost_putle16(uint8_t *dest, uint16_t val);

static inline int usbhost_devdesc(const struct usb_devdesc_s *devdesc, FAR struct usbhost_id_s *id);
static inline int usbhost_configdesc(const uint8_t *configdesc, int desclen, FAR struct usbhost_id_s *id);
static inline int usbhost_classbind(FAR struct usbhost_hubport_s *hport, FAR const uint8_t *configdesc, int desclen, FAR struct usbhost_id_s *id, FAR struct usbhost_class_s **devclass);

/****************************************************************************
 * Private Data
 ****************************************************************************/

/****************************************************************************
 * Public Data
 ****************************************************************************/

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: usbhost_getle16
 *
 * Description:
 *   Get a (possibly unaligned) 16-bit little endian value.
 *
 ****************************************************************************/

static inline uint16_t usbhost_getle16(const uint8_t *val)
{
	return (uint16_t)val[1] << 8 | (uint16_t)val[0];
}

/****************************************************************************
 * Name: usbhost_putle16
 *
 * Description:
 *   Put a (possibly unaligned) 16-bit little endian value.
 *
 ****************************************************************************/

static void usbhost_putle16(uint8_t *dest, uint16_t val)
{
	dest[0] = val & 0xff;		/* Little endian means LS byte first in byte stream */
	dest[1] = val >> 8;
}

/****************************************************************************
 * Name: usbhost_devdesc
 *
 * Description:
 *   A configuration descriptor has been obtained from the device.  Find the
 *   ID information for the class that supports this device.
 *
 ****************************************************************************/

static inline int usbhost_devdesc(FAR const struct usb_devdesc_s *devdesc, FAR struct usbhost_id_s *id)
{
	/* Clear the ID info */

	memset(id, 0, sizeof(struct usbhost_id_s));

	/* Pick off the class ID info */

	id->base = devdesc->classid;
	id->subclass = devdesc->subclass;
	id->proto = devdesc->protocol;

	/* Pick off the VID and PID as well (for vendor specfic devices) */

	id->vid = usbhost_getle16(devdesc->vendor);
	id->pid = usbhost_getle16(devdesc->product);

	uvdbg("class:%d subclass:%04x protocol:%04x vid:%d pid:%d\n", id->base, id->subclass, id->proto, id->vid, id->pid);
	return OK;
}

/****************************************************************************
 * Name: usbhost_configdesc
 *
 * Description:
 *   A configuration descriptor has been obtained from the device.  Find the
 *   ID information for the class that supports this device.
 *
 ****************************************************************************/

static inline int usbhost_configdesc(const uint8_t *configdesc, int cfglen, struct usbhost_id_s *id)
{
	FAR struct usb_cfgdesc_s *cfgdesc;
	FAR struct usb_ifdesc_s *ifdesc;
	int remaining;

	DEBUGASSERT(configdesc != NULL && cfglen >= USB_SIZEOF_CFGDESC);

	/* Verify that we were passed a configuration descriptor */

	cfgdesc = (struct usb_cfgdesc_s *)configdesc;
	uvdbg("cfg len:%d total len:%d\n", cfgdesc->len, cfglen);

	if (cfgdesc->type != USB_DESC_TYPE_CONFIG) {
		return -EINVAL;
	}

	/* Skip to the next entry descriptor */

	configdesc += cfgdesc->len;
	remaining = cfglen - cfgdesc->len;

	/* Loop while there are more descriptors to examine */

	memset(id, 0, sizeof(FAR struct usb_desc_s));
	while (remaining >= sizeof(struct usb_desc_s)) {
		/* What is the next descriptor? Is it an interface descriptor? */

		ifdesc = (struct usb_ifdesc_s *)configdesc;
		if (ifdesc->type == USB_DESC_TYPE_INTERFACE) {
			/* Yes, extract the class information from the interface descriptor.
			 * Typically these values are zero meaning that the "real" ID
			 * information resides in the device descriptor.
			 */

			DEBUGASSERT(remaining >= sizeof(struct usb_ifdesc_s));
			id->base = ifdesc->classid;
			id->subclass = ifdesc->subclass;
			id->proto = ifdesc->protocol;
			uvdbg("class:%d subclass:%d protocol:%d\n", id->base, id->subclass, id->proto);
			return OK;
		}

		/* Increment the address of the next descriptor */

		configdesc += ifdesc->len;
		remaining -= ifdesc->len;
	}

	return -ENOENT;
}

/****************************************************************************
 * Name: usbhost_classbind
 *
 * Description:
 *   A configuration descriptor has been obtained from the device.  Try to
 *   bind this configuration descriptor with a supported class.
 *
 ****************************************************************************/

static inline int usbhost_classbind(FAR struct usbhost_hubport_s *hport, const uint8_t *configdesc, int desclen, struct usbhost_id_s *id, FAR struct usbhost_class_s **usbclass)
{
	FAR struct usbhost_class_s *devclass;
	FAR const struct usbhost_registry_s *reg;
	int ret = -EINVAL;

	/* Is there is a class implementation registered to support this device. */

	reg = usbhost_findclass(id);
	uvdbg("usbhost_findclass: %p\n", reg);
	if (reg != NULL) {
		/* Yes.. there is a class for this device.  Get an instance of
		 * its interface.
		 */

		ret = -ENOMEM;
		devclass = CLASS_CREATE(reg, hport, id);
		uvdbg("CLASS_CREATE: %p\n", devclass);
		if (devclass != NULL) {
			/* Then bind the newly instantiated class instance */

			ret = CLASS_CONNECT(devclass, configdesc, desclen);
			if (ret < 0) {
				/* On failures, call the class disconnect method which
				 * should then free the allocated devclass instance.
				 */

				udbg("CLASS_CONNECT failed: %d\n", ret);
				CLASS_DISCONNECTED(devclass);
			} else {
				*usbclass = devclass;
			}
		}
	}

	uvdbg("Returning: %d\n", ret);
	return ret;
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: usbhost_enumerate
 *
 * Description:
 *   Enumerate the connected device.  As part of this enumeration process,
 *   the driver will (1) get the device's configuration descriptor, (2)
 *   extract the class ID info from the configuration descriptor, (3) call
 *   usbhost_findclass() to find the class that supports this device, (4)
 *   call the create() method on the struct usbhost_registry_s interface
 *   to get a class instance, and finally (5) call the configdesc() method
 *   of the struct usbhost_class_s interface.  After that, the class is in
 *   charge of the sequence of operations.
 *
 * Input Parameters:
 *   hport - The hub port that manages the new class.
 *   devclass - If the class driver for the device is successful located
 *      and bound to the hub port, the allocated class instance is returned
 *      into this caller-provided memory location.
 *
 * Returned Values:
 *   On success, zero (OK) is returned. On a failure, a negated errno value is
 *   returned indicating the nature of the failure
 *
 * Assumptions:
 *   - Only a single class bound to a single device is supported.
 *   - Called from a single thread so no mutual exclusion is required.
 *   - Never called from an interrupt handler.
 *
 ****************************************************************************/

int usbhost_enumerate(FAR struct usbhost_hubport_s *hport, FAR struct usbhost_class_s **devclass)
{
	FAR struct usb_ctrlreq_s *ctrlreq = NULL;
	struct usbhost_id_s id;
	size_t maxlen;
	unsigned int cfglen;
	uint8_t maxpacketsize;
	uint8_t descsize;
	uint8_t funcaddr = 0;
	FAR uint8_t *buffer = NULL;
	int ret;

	DEBUGASSERT(hport != NULL && hport->drvr != NULL);

	/* Allocate descriptor buffers for use in this function.  We will need two:
	 * One for the request and one for the data buffer.
	 */

	ret = DRVR_ALLOC(hport->drvr, (FAR uint8_t **) & ctrlreq, &maxlen);
	if (ret < 0) {
		udbg("DRVR_ALLOC failed: %d\n", ret);
		return ret;
	}

	ret = DRVR_ALLOC(hport->drvr, &buffer, &maxlen);
	if (ret < 0) {
		udbg("DRVR_ALLOC failed: %d\n", ret);
		goto errout;
	}

	/* Pick an appropriate packet size for this device
	 *
	 * USB 2.0, Paragraph 5.5.3 "Control Transfer Packet Size Constraints"
	 *
	 *  "An endpoint for control transfers specifies the maximum data
	 *   payload size that the endpoint can accept from or transmit to
	 *   the bus. The allowable maximum control transfer data payload
	 *   sizes for full-speed devices is 8, 16, 32, or 64 bytes; for
	 *   high-speed devices, it is 64 bytes and for low-speed devices,
	 *   it is 8 bytes. This maximum applies to the data payloads of the
	 *   Data packets following a Setup..."
	 */

	if (hport->speed == USB_SPEED_HIGH) {
		/* For high-speed, we must use 64 bytes */

		maxpacketsize = 64;
		descsize = USB_SIZEOF_DEVDESC;
	} else {
		/* Eight will work for both low- and full-speed */

		maxpacketsize = 8;
		descsize = 8;
	}

	/* Configure EP0 with the initial maximum packet size */

	DRVR_EP0CONFIGURE(hport->drvr, hport->ep0, 0, hport->speed, maxpacketsize);

	/* Read first bytes of the device descriptor */

	ctrlreq->type = USB_REQ_DIR_IN | USB_REQ_RECIPIENT_DEVICE;
	ctrlreq->req = USB_REQ_GETDESCRIPTOR;
	usbhost_putle16(ctrlreq->value, (USB_DESC_TYPE_DEVICE << 8));
	usbhost_putle16(ctrlreq->index, 0);
	usbhost_putle16(ctrlreq->len, descsize);

	ret = DRVR_CTRLIN(hport->drvr, hport->ep0, ctrlreq, buffer);
	if (ret < 0) {
		udbg("ERROR: Failed to get device descriptor, length=%d: %d\n", descsize, ret);
		goto errout;
	}

	/* Extract the correct max packetsize from the device descriptor */

	maxpacketsize = ((struct usb_devdesc_s *)buffer)->mxpacketsize;
	uvdbg("maxpacksetsize: %d\n", maxpacketsize);

	/* And reconfigure EP0 with the correct maximum packet size */

	DRVR_EP0CONFIGURE(hport->drvr, hport->ep0, 0, hport->speed, maxpacketsize);

	/* Now read the full device descriptor (if we have not already done so) */

	if (descsize < USB_SIZEOF_DEVDESC) {
		ctrlreq->type = USB_REQ_DIR_IN | USB_REQ_RECIPIENT_DEVICE;
		ctrlreq->req = USB_REQ_GETDESCRIPTOR;
		usbhost_putle16(ctrlreq->value, (USB_DESC_TYPE_DEVICE << 8));
		usbhost_putle16(ctrlreq->index, 0);
		usbhost_putle16(ctrlreq->len, USB_SIZEOF_DEVDESC);

		ret = DRVR_CTRLIN(hport->drvr, hport->ep0, ctrlreq, buffer);
		if (ret < 0) {
			udbg("ERROR: Failed to get device descriptor, length=%d: %d\n", USB_SIZEOF_DEVDESC, ret);
			goto errout;
		}
	}

	/* Get class identification information from the device descriptor.  Most
	 * devices set this to USB_CLASS_PER_INTERFACE (zero) and provide the
	 * identification information in the interface descriptor(s).  That allows
	 * a device to support multiple, different classes.
	 */

	(void)usbhost_devdesc((struct usb_devdesc_s *)buffer, &id);

	/* Assign a function address to the device connected to this port */

	funcaddr = usbhost_devaddr_create(hport);
	if (funcaddr < 0) {
		udbg("ERROR: usbhost_devaddr_create failed: %d\n", ret);
		goto errout;
	}

	/* Set the USB device address */

	ctrlreq->type = USB_REQ_DIR_OUT | USB_REQ_RECIPIENT_DEVICE;
	ctrlreq->req = USB_REQ_SETADDRESS;
	usbhost_putle16(ctrlreq->value, (uint16_t)funcaddr);
	usbhost_putle16(ctrlreq->index, 0);
	usbhost_putle16(ctrlreq->len, 0);

	ret = DRVR_CTRLOUT(hport->drvr, hport->ep0, ctrlreq, NULL);
	if (ret < 0) {
		udbg("ERROR: Failed to set address: %d\n");
		goto errout;
	}

	usleep(2 * 1000);

	/* Assign the function address to the port */

	DEBUGASSERT(hport->funcaddr == 0 && funcaddr != 0);
	hport->funcaddr = funcaddr;

	/* And reconfigure EP0 with the correct address */

	DRVR_EP0CONFIGURE(hport->drvr, hport->ep0, hport->funcaddr, hport->speed, maxpacketsize);

	/* Get the configuration descriptor (only), index == 0.  Should not be
	 * hard-coded! More logic is needed in order to handle devices with
	 * multiple configurations.
	 */

	ctrlreq->type = USB_REQ_DIR_IN | USB_REQ_RECIPIENT_DEVICE;
	ctrlreq->req = USB_REQ_GETDESCRIPTOR;
	usbhost_putle16(ctrlreq->value, (USB_DESC_TYPE_CONFIG << 8));
	usbhost_putle16(ctrlreq->index, 0);
	usbhost_putle16(ctrlreq->len, USB_SIZEOF_CFGDESC);

	ret = DRVR_CTRLIN(hport->drvr, hport->ep0, ctrlreq, buffer);
	if (ret < 0) {
		udbg("ERROR: Failed to get configuration descriptor, length=%d: %d\n", USB_SIZEOF_CFGDESC, ret);
		goto errout;
	}

	/* Extract the full size of the configuration data */

	cfglen = (unsigned int)usbhost_getle16(((struct usb_cfgdesc_s *)buffer)->totallen);
	uvdbg("sizeof config data: %d\n", cfglen);

	/* Get all of the configuration descriptor data, index == 0 (Should not be
	 * hard-coded!)
	 */

	ctrlreq->type = USB_REQ_DIR_IN | USB_REQ_RECIPIENT_DEVICE;
	ctrlreq->req = USB_REQ_GETDESCRIPTOR;
	usbhost_putle16(ctrlreq->value, (USB_DESC_TYPE_CONFIG << 8));
	usbhost_putle16(ctrlreq->index, 0);
	usbhost_putle16(ctrlreq->len, cfglen);

	ret = DRVR_CTRLIN(hport->drvr, hport->ep0, ctrlreq, buffer);
	if (ret < 0) {
		udbg("ERROR: Failed to get configuration descriptor, length=%d: %d\n", cfglen, ret);
		goto errout;
	}

	/* Select device configuration 1 (Should not be hard-coded!) */

	ctrlreq->type = USB_REQ_DIR_OUT | USB_REQ_RECIPIENT_DEVICE;
	ctrlreq->req = USB_REQ_SETCONFIGURATION;
	usbhost_putle16(ctrlreq->value, 1);
	usbhost_putle16(ctrlreq->index, 0);
	usbhost_putle16(ctrlreq->len, 0);

	ret = DRVR_CTRLOUT(hport->drvr, hport->ep0, ctrlreq, NULL);
	if (ret < 0) {
		udbg("ERROR: Failed to set configuration: %d\n", ret);
		goto errout;
	}

	/* Was the class identification information provided in the device
	 * descriptor? Or do we need to find it in the interface descriptor(s)?
	 */

	if (id.base == USB_CLASS_PER_INTERFACE) {
		/* Get the class identification information for this device from the
		 * interface descriptor(s).  Hmmm.. More logic is need to handle the
		 * case of multiple interface descriptors.
		 */

		ret = usbhost_configdesc(buffer, cfglen, &id);
		if (ret < 0) {
			udbg("ERROR: usbhost_configdesc failed: %d\n", ret);
			goto errout;
		}
	}

	/* Some devices may require some delay before initialization */

	usleep(100 * 1000);

	/* Parse the configuration descriptor and bind to the class instance for the
	 * device.  This needs to be the last thing done because the class driver
	 * will begin configuring the device.
	 */

	ret = usbhost_classbind(hport, buffer, cfglen, &id, devclass);
	if (ret < 0) {
		udbg("ERROR: usbhost_classbind failed %d\n", ret);
	}

errout:
	if (ret < 0) {
		/* Release the device function address on any failure */

		usbhost_devaddr_destroy(hport, funcaddr);
		hport->funcaddr = 0;
	}

	/* Release temporary buffers in any event */

	if (buffer != NULL) {
		DRVR_FREE(hport->drvr, buffer);
	}

	if (ctrlreq) {
		DRVR_FREE(hport->drvr, (FAR uint8_t *) ctrlreq);
	}

	return ret;
}
